The present invention relates in general terms to testing (checking) systems used for the automatic testing of the characteristics and/or operating conditions of electrical and/or electronic circuits.
More specifically, an embodiment of the invention has been developed for possible application in the automotive sector in order to provide an automatic testing station which can stimulate electronic control units (E.C.U.s) of vehicles by simulating, during bench testing, the conditions present in vehicles in order to check whether or not they are operating correctly.
In order fully to satisfy the requirements of use, such an automatic testing system must offer the possibility of preparing functional tests for a generic control unit in the laboratory without the need necessarily to carry out tests on the vehicle, thus avoiding the following disadvantages:
practical difficulties in preparing for the test (availability of the prototype vehicle, non-optimal operation of the prototype . . . ), PA1 testing which is not always exhaustive (difficulties in the generation of anomalous conditions, possibility of damaging parts of the vehicle involved in the test), and PA1 risks to the testers in promoting the malfunctioning of devices of the vehicle. PA1 the ability to test a generic control unit rapidly, PA1 the ability to reproduce the tests in a predetermined sequence, PA1 the ability to carry out tests on control units under different climatic conditions by the modification of temperature and humidity, and PA1 the immediate availability of documentation relating to the results of the tests carried out. PA1 a subsystem for stimulating the control unit under test, and PA1 a subsystem for decoding and analysing messages transmitted by the control unit under test through a serial diagnostic channel. PA1 repetitive analog signals of arbitrary form which are variable in frequency and in amplitude (for example signals indicative of the passage through top dead center, of the phase of the engine etc . . . ), PA1 non-repetitive analog signals of arbitrary form, which are variable in amplitude and in frequency (for example signals indicative of the vacuum in the intake manifold, of the position of the carburettor throttle valve, . . . ), PA1 on/off signals which are variable in amplitude or in frequency (for example steering sensor, accelerometer . . . ), and PA1 signals which simulate resistive transducers (for example NTC or PTC transducers . . . ). PA1 a single identification of the signal, PA1 the instrument which is to generate or check the signal, and PA1 a description of the signal, defined as the set of information necessary for the instrument to generate or check the signal correctly.
The advantages to be provided are therefore:
An object of the present invention is therefore to provide a testing system which achieves the above advantages while avoiding the disadvantages described above.